From: Kefu Chai <kchai@redhat.com>
Date: Sat, 24 Aug 2019 15:41:57 +0000 (+0800)
Subject: rgw: RGWObjManifest::obj_iterator::seek always update locations
X-Git-Tag: v15.1.0~1760^2~9
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=6833234fd29646d4130c974c457a8c7ded85239e;p=ceph.git

rgw: RGWObjManifest::obj_iterator::seek always update locations

we should update explicit loc and location even if
`ofs >= manifest->obj_size`. there is chance that we are updating an end
iterator whose ofs is equal to obj_size. before being updated, the end
iterator points to an implicit location, while after being updated, the
manifest could be using an explicit location, so we should update the
end iterator as well.

Fixes: https://tracker.ceph.com/issues/41416
Signed-off-by: Kefu Chai <kchai@redhat.com>
---

diff --git a/src/rgw/rgw_dencoder.cc b/src/rgw/rgw_dencoder.cc
index 4fef224f33e..461741ce5d9 100644
--- a/src/rgw/rgw_dencoder.cc
+++ b/src/rgw/rgw_dencoder.cc
@@ -48,11 +48,11 @@ void RGWObjManifest::obj_iterator::seek(uint64_t o)
     if (explicit_iter != manifest->objs.begin()) {
       --explicit_iter;
     }
-    if (ofs >= manifest->obj_size) {
+    if (ofs < manifest->obj_size) {
+      update_explicit_pos();
+    } else {
       ofs = manifest->obj_size;
-      return;
     }
-    update_explicit_pos();
     update_location();
     return;
   }
@@ -116,7 +116,11 @@ void RGWObjManifest::obj_iterator::seek(uint64_t o)
 void RGWObjManifest::obj_iterator::update_location()
 {
   if (manifest->explicit_objs) {
-    location = explicit_iter->second.loc;
+    if (manifest->empty()) {
+      location = rgw_obj_select{};
+    } else {
+      location = explicit_iter->second.loc;
+    }
     return;
   }
 
diff --git a/src/rgw/rgw_obj_manifest.h b/src/rgw/rgw_obj_manifest.h
index 59abaf36abe..942ecb63b6e 100644
--- a/src/rgw/rgw_obj_manifest.h
+++ b/src/rgw/rgw_obj_manifest.h
@@ -451,9 +451,7 @@ public:
       : obj_iterator(_m, 0)
     {}
     obj_iterator(RGWObjManifest *_m, uint64_t _ofs) : manifest(_m) {
-      if (!manifest->empty()) {
-        seek(_ofs);
-      }
+      seek(_ofs);
     }
     void seek(uint64_t ofs);